Piston-packing



(NoModeLj I H. L. ST. JAMES.

PISTON PACKING.

No.'377,442q Patented Feb. 7, 1888 5-? iwwi A 2;? 1i T: 1

WITNESSES aZLu zZ-%wZZ v A I To all whom it may concern:

,UNITED STATES 7 PATENT Orrici af HENRY L. ST. JAMES, on MARSHALL,TEXAS.

'PISTON-PA'CIKING.

SPECIFICATION forming part of Letters Patent No. 377.44g, dated February'1, 188 8.

Application filed October 28, 1887.

Beit known that LHENRY L. $1. JAMES, of Marshall, in the county ofHarrison and State of Texas, have invented a new and useful Improvementin Steam Piston-Packingpand I do hereby declare-that the following is afull and exact descriptionof the same, reference being had to theaccompanying drawings, and

to the letters of reference marked thereon.

This invention relates to certain novel improvements in steampiston-packing, which improvements will be fully understood from thefollowing description and claims, when taken in connection with theannexed draw: ings,in whichv v I Figure 1 is a side view of the improvedpiston and its packing. Fig. 2 is a diametrical section through Fig. 1,taken in the plane indicated by dotted line :10 a: on Fig. 3. Fig. 3 isa section through Fig. 1, taken inthe plane indicated by dotted line y ythereon. Fig. 4 is a sectional view of one of the piston-packingsegments, showing the packing-rings on the stem thereof. Fig. 5 is adetail of one of the cut rings. Fig. 6 is a sectional detail of thepiston-stem. p

Referring'to the annexed drawings, A designates a piston-head, and Bdesignates the piston-rod thereof. The piston-head, the peculiarities ofwhich I shall hereinafter describe, is bored out straight, and the rod Bis constructed with a cylindrical entering portion,

B, having a shoulder at a and an annular flange at b. When this rod isdriven into the piston, the latter is shrunk on it, after which theflange ais riveted into a countersink in the face of the piston, therebypositively connecting the piston to its rod without the use of nuts,andleaving theface of the piston and the end of its rod flush. Thepiston-head is cast entire, and it has two annular grooves in itscircumference, which grooves are lettered c c, and they are separated byan annular septum, d. For the purpose of description,' the piston-headis divided into twopartsin planes at right angles to the longitudinalaxis of the rod B, one of which "planes is represented in the sectionalview, Fig. 3. The parts on the opposite side of the septum d are exactlylike those which I am about to particularly specify. ii

0 designates an interior hub, which is beand provided with suitabletween the face and back plates, 6 e. From this Serial No.253, 602, (Nomodel.)

hub .radiatesix or any otherlsuitable number of arms or brackets, f,which re-enforce the piston, and whichare radially with respect to theaxis of the piston-head A bored out to points suitably near the hub,from which points the front and back plates have steamports passingthrough them and lettered g g.

D D designateT-shaped segmental pistons,

the cylindrical rods hLot' which enter the bores v in the radial arms orbrackets f, and'are each provided near theirinner ends with annulargrooves 2", in which are applied spring packing-rings j, the cuts ofwhich break j'oints. The ends of the segmental portions of said segmentsdo not touch each other, and, collectively, these segments make up. anexpansible bearing for a split ring, G, which incloses' them and affordsthe expansible elastic pack-' ing proper'and the wearing-surfaceof thepiston. =The ends of the cylindricalrods hhavecentralapertures,n,extendingintothem, I. v

a short'distance from which radiate apertures n, that adniitst'eam intothe groovesi to'expand the ringsj and pack them steanrtight against thebores in the radial arms f.

It willbe observed that the pistonhead is cored from the slots It to thehub on both sides of the septum d, thereby leaving an unbroken flatsurface to the steam at both ends of the piston. By thus coring out Irender unnecessary'the subsequent plugging of the end platesof the.pistonhead.

' Having described niyinvention,lclaim 1. The within-described pistonhead cast entire and having radial arms bored out, in combination withthe piston-segments, the steamports in the piston-plates, and stems ofsaid segments, packing'expans'ible rings .on said stems, and theexpans'ible packing-rings inclosing the said piston-segments,substantially asdescribed. v r I 2. A piston-head cast entire andcored'out the radial arms, the steam-ports g, and the T- .95 from itsslots to its hub, in combination with shaped pistons having'rodsperforated atn a,

packing-rings,substantially as described.

Intestimony whereof-I affix mysignature in presence of two witnesses.

HENRY L, ST. J AMES': Witnesses: J. H. HUDSON, F. O. COLEMAN- IOO

